org.metawidget.statically.jsp.widgetbuilder.JspWidgetBuilder Maven / Gradle / Ivy
// Metawidget
//
// For historical reasons, this file is licensed under the LGPL
// (http://www.gnu.org/licenses/lgpl-2.1.html).
//
// Most other files in Metawidget are licensed under both the
// LGPL/EPL and a commercial license. See http://metawidget.org
// for details.
package org.metawidget.statically.jsp.widgetbuilder;
import static org.metawidget.inspector.InspectionResultConstants.*;
import static org.metawidget.inspector.jsp.JspInspectionResultConstants.*;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import org.metawidget.statically.StaticXmlMetawidget;
import org.metawidget.statically.StaticXmlWidget;
import org.metawidget.statically.html.widgetbuilder.HtmlOption;
import org.metawidget.statically.html.widgetbuilder.HtmlSelect;
import org.metawidget.statically.html.widgetbuilder.HtmlTable;
import org.metawidget.statically.html.widgetbuilder.HtmlTableBody;
import org.metawidget.statically.html.widgetbuilder.HtmlTableCell;
import org.metawidget.statically.html.widgetbuilder.HtmlTableHead;
import org.metawidget.statically.html.widgetbuilder.HtmlTableHeader;
import org.metawidget.statically.html.widgetbuilder.HtmlTableRow;
import org.metawidget.statically.jsp.StaticJspMetawidget;
import org.metawidget.statically.jsp.StaticJspUtils;
import org.metawidget.statically.layout.SimpleLayout;
import org.metawidget.util.CollectionUtils;
import org.metawidget.util.WidgetBuilderUtils;
import org.metawidget.util.XmlUtils;
import org.metawidget.util.simple.StringUtils;
import org.metawidget.widgetbuilder.iface.WidgetBuilder;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
/**
* @author Richard Kennard
* @author Ryan Bradley
*/
public class JspWidgetBuilder
implements WidgetBuilder {
//
// Private members
//
private final int mMaximumColumnsInDataTable;
//
// Constructor
//
public JspWidgetBuilder() {
this( new JspWidgetBuilderConfig() );
}
public JspWidgetBuilder( JspWidgetBuilderConfig config ) {
mMaximumColumnsInDataTable = config.getMaximumColumnsInDataTable();
}
//
// Public methods
//
public StaticXmlWidget buildWidget( String elementName, Map attributes, StaticXmlMetawidget metawidget ) {
// Not for us?
if ( TRUE.equals( attributes.get( HIDDEN ) ) ) {
return null;
}
// Action
if ( ACTION.equals( elementName ) ) {
return null;
}
// JSP Lookup
String jspLookup = attributes.get( JSP_LOOKUP );
if ( jspLookup != null && !"".equals( jspLookup ) ) {
HtmlSelect select = new HtmlSelect();
addSelectItems( select, jspLookup, attributes );
return select;
}
// Lookup the Class
Class clazz = WidgetBuilderUtils.getActualClassOrType( attributes, null );
if ( clazz != null ) {
// Support Collections and Arrays (c:forEach can handle either)
if ( Collection.class.isAssignableFrom( clazz ) || clazz.isArray() ) {
return createDataTableComponent( elementName, attributes, metawidget );
}
}
// Not for us
return null;
}
//
// Protected methods
//
/**
* @param elementName
* such as ENTITY or PROPERTY. Can be useful in determining how to construct the EL
* for the table.
*/
protected StaticXmlWidget createDataTableComponent( String elementName, Map attributes, StaticXmlMetawidget metawidget ) {
HtmlTable table = new HtmlTable();
CoreForEach forEach = new CoreForEach();
String items = attributes.get( NAME );
if ( items != null ) {
items = StaticJspUtils.wrapExpression( items );
}
forEach.putAttribute( "items", items );
String var = "item";
forEach.putAttribute( "var", var );
// Add a section for table headers.
HtmlTableHead tableHead = new HtmlTableHead();
table.getChildren().add( tableHead );
tableHead.getChildren().add( new HtmlTableRow() );
HtmlTableBody body = new HtmlTableBody();
body.getChildren().add( forEach );
table.getChildren().add( body );
// Inspect the component type.
String componentType = WidgetBuilderUtils.getComponentType( attributes );
String inspectedType = null;
if ( componentType != null ) {
inspectedType = metawidget.inspect( null, componentType, (String[]) null );
}
// If there is no type...
if ( inspectedType == null ) {
// ...resort to a single column table...
HtmlTableRow row = new HtmlTableRow();
forEach.getChildren().add( row );
Map columnAttributes = CollectionUtils.newHashMap();
columnAttributes.put( NAME, attributes.get( NAME ) );
addColumnComponent( row, forEach, attributes, ENTITY, columnAttributes, metawidget );
} else {
// ...otherwise, iterate over the component type and add multiple columns.
Element root = XmlUtils.documentFromString( inspectedType ).getDocumentElement();
NodeList elements = root.getFirstChild().getChildNodes();
addColumnComponents( table, forEach, attributes, elements, metawidget );
}
return table;
}
/**
* Adds column components to the given table.
*
* Clients can override this method to add additional columns, such as a 'Delete' button.
*/
protected void addColumnComponents( HtmlTable table, CoreForEach forEach, Map attributes, NodeList elements, StaticXmlMetawidget metawidget ) {
// At first, only add columns for the 'required' fields
boolean onlyRequired = true;
while ( true ) {
// Create a new row for the forEach tag to iterate upon.
HtmlTableRow row = new HtmlTableRow();
// For each property...
for ( int i = 0; i < elements.getLength(); i++ ) {
Node node = elements.item( i );
if ( !( node instanceof Element ) ) {
continue;
}
Element element = (Element) node;
// ...(not action)...
if ( ACTION.equals( element.getNodeName() ) ) {
continue;
}
// ...that is visible...
if ( TRUE.equals( element.getAttribute( HIDDEN ) ) ) {
continue;
}
// ...and is required...
//
// Note: this is a controversial choice. Our logic is that a) we need to limit
// the number of columns somehow, and b) displaying all the required fields should
// be enough to uniquely identify the row to the user. However, users may wish
// to override this default behaviour
if ( onlyRequired && !TRUE.equals( element.getAttribute( REQUIRED ) ) ) {
continue;
}
// ...add a column...
addColumnComponent( row, forEach, attributes, PROPERTY, XmlUtils.getAttributesAsMap( element ), metawidget );
// ...and a header for that column...
addColumnHeader( table, XmlUtils.getAttributesAsMap( element ), metawidget );
// ...up to a sensible maximum.
if ( row.getChildren().size() == mMaximumColumnsInDataTable ) {
break;
}
}
if ( !row.getChildren().isEmpty() ) {
forEach.getChildren().add( row );
}
// If we couldn't add any 'required' columns, try again for every field.
if ( !forEach.getChildren().isEmpty() || !onlyRequired ) {
break;
}
onlyRequired = false;
}
}
protected void addColumnHeader( HtmlTable table, Map attributes, StaticXmlMetawidget metawidget ) {
HtmlTableHeader header = new HtmlTableHeader();
header.setTextContent( metawidget.getLabelString( attributes ) );
table.getChildren().get( 0 ).getChildren().get( 0 ).getChildren().add( header );
}
/**
* Add an HtmlColumn component for the given attributes, to the given HtmlDataTable.
*
* Clients can override this method to modify the column contents. For example, to place a link
* around the text.
*
* @param tableAttributes
* the metadata attributes used to render the parent table. May be useful for
* determining the overall type of the row
*/
protected void addColumnComponent( HtmlTableRow row, CoreForEach forEach, Map tableAttributes, String elementName, Map columnAttributes, StaticXmlMetawidget metawidget ) {
// Add a new column to the current row of the table.
HtmlTableCell cell = new HtmlTableCell();
row.getChildren().add( cell );
StaticXmlWidget columnContents;
// Make the column contents...
if ( ENTITY.equals( elementName )) {
columnContents = new CoreOut();
columnContents.putAttribute( "value", StaticJspUtils.wrapExpression( forEach.getAttribute( "var" ) ) );
} else {
// ...using a nested Metawidget if we can
columnContents = new StaticJspMetawidget();
String valueExpression = forEach.getAttribute( "var" ) + StringUtils.SEPARATOR_DOT_CHAR + StringUtils.decapitalize( columnAttributes.get( NAME ) );
columnContents.putAttribute( "value", StaticJspUtils.wrapExpression( valueExpression ) );
StaticJspMetawidget columnMetawidget = (StaticJspMetawidget) columnContents;
columnMetawidget.setPath( WidgetBuilderUtils.getComponentType( tableAttributes ) + StringUtils.SEPARATOR_FORWARD_SLASH_CHAR + columnAttributes.get( NAME ) );
metawidget.initNestedMetawidget( columnMetawidget, columnAttributes );
columnMetawidget.setLayout( new SimpleLayout() );
columnMetawidget.setReadOnly( true );
}
cell.getChildren().add( columnContents );
}
protected void addSelectItems( HtmlSelect select, String valueExpression, Map attributes ) {
// Empty option
if ( WidgetBuilderUtils.needsEmptyLookupItem( attributes ) ) {
addSelectItem( select, "", null );
}
addSelectItem( select, valueExpression, null );
}
protected void addSelectItems( HtmlSelect select, List values, List labels, Map attributes ) {
if ( values == null ) {
return;
}
// Empty option.
if ( WidgetBuilderUtils.needsEmptyLookupItem( attributes ) ) {
addSelectItem( select, "", null );
}
// Add the rest of the select items.
for ( int i = 0, length = values.size(); i < length; i++ ) {
String value = values.get( i );
String label = null;
if ( labels != null && !labels.isEmpty() ) {
label = labels.get( i );
}
addSelectItem( select, value, label );
}
return;
}
//
// Private methods
//
private void addSelectItem( HtmlSelect select, String value, String label ) {
HtmlOption selectItem = new HtmlOption();
selectItem.putAttribute( "value", value );
if ( label != null ) {
selectItem.setTextContent( label );
}
select.getChildren().add( selectItem );
return;
}
}